Ace Glass 8769-20 Automatic Pressure Relief Valve with Whistle

Automatic, adjustable pressure release valve for safer operation of pilot plant or other assemblies where the pressure is of great concern. The tension on the stainless steel spring determines the amount of pressure needed to force the lower piece open. With the spring supplied, the range is 15-50 psi. Comes with warning whistle. Plunger made of PTFE with FETFE O-Rings.